NOT APPLICABLE
NOT APPLICABLE
NOT APPLICABLE
The typical door knob assembly consists of opposing doorknobs secured to the edge of a door through a cutout in the door. A bore is drilled from the front edge of the door to the cutout, and defines a path along which the door latch bolt travels. While use of these standard doorknobs is convenient in a finished building, such devices create issues when the building is under construction.
During construction, many contractors need to access the building site. When a door is first installed, it is installed without the door locks. The door locks are usually installed as part of the finish work. Since no door latch exists, the doors are allowed to freely swing in the wind. This frequently results in damage to the door, doorjamb and wall surfaces that the door may strike.
There are a number of options utilized for reducing or eliminating the damage potentially caused by such unsecured doors. One option is for a builder to shim the door shut or nail studs across the door to prevent the door from swinging open. This is inconvenient as the contractors accessing the premises must remove the shims or studs each time they access the premises, and the shims and/or studs must be re-attached when the contractor leaves. Such constant shimming or securing of the door can also result in damage to the door system and walls. With the confusion of many contractors on site at the same time, the door is frequently left unsecured when everyone has left the premises, leaving the door system and walls vulnerable to damage.
Another option is to install traditional doorknobs on a temporary basis. This is both inconvenient for the builder and expensive. Because the doors must remain unlocked to permit access to the premises by all contractors working in the building, the locks can be removed. Additionally, if the wind should catch the door and the door swings hard against a finished wall, the knobs tend to damage the walls, unless door stops are also installed. Additionally, sometimes contractors lock the outside door, which renders it impossible for the next contractor arriving at the premises without a key to obtain access to the building.
A further problem with installing temporary doorknobs during construction arises when the door is being painted. When painted, the doorknobs must be removed for the door to be properly painted, which again allows the door to swing freely, now with wet paint. In addition to the potential damage to the door and walls, the quality of the paint job is jeopardized.
The present door latch assembly is of two piece, plastic construction secured together with a common rubber band and is designed to be internally mounted within the bore and cutout of a standard hinged door. The door latch includes a one piece, plastic tubular casing with a latch plate formed at one end. The casing defines an internal guide path for receipt and movement of a latch bolt. A latch bolt is slidably mounted in the tubular casing with sufficient travel to protrude therefrom for latching engagement with an associated striker plate attached to the door jamb. An xe2x80x9cOxe2x80x9d ring is formed at the inward facing end of the latch bolt, which is accessible through the door cutout, so that the door latch may be retracted into the casing by digital movement of the xe2x80x9cOxe2x80x9d ring. The rubber band is attached to the casing and latch bolt to bias the latch bolt in a position causing part of the latch bolt to protrude from the casing for latching, yet allows manual retraction of the latch bolt within the casing.
One object of the invention is to provide an inexpensive plastic lock which is simple to install and remove, yet is durable and reliable when used in new construction.
Another object of the invention is to minimize the vulnerability of the door and structure to damage if the door should swing free.
Yet another object of the invention is to allow the door to be painted, without loss of the ability to secure the door in closed position.
Yet another object of the invention is to create a door latch which is easy to use by contractors who need to bring bulky or heavy product through the doorway.
Still another object of the invention is to provide a lock mechanism constructed primarily of molded plastic resin material, with a minimum number of parts for easy assembly, installation, use and removable.
With these and other objects in view, the invention consists of the construction, arrangement and combination of the various parts of the lock mechanism in a manner intended to attain the objects contemplated herein.